Electrical locking receptacl



Nov. 26, 1940.

A. L. KUHLMAN' ELECTRICAL LOCKING RECEPTACLE Filed July 5, 1939ATTORNEY.

Patented Nov. 26, 1940 UNITED STATES/ PATENT OFFICE T 2{222,71s

ELECTRICAL LOCKING rmcEP'rAcLl Arthur L. nhuman, Ann Arbor, Mich.Application July 5, 1939, Serial No. 282,837

4 Claims. (Cl. 173-328) This invention relates to a receptacle adaptedto receive the prongs of a plug and to rigidly se cure said prongs inposition.

One of the prime objects of the invention is to 6 design a simple,practical and eflicient receptacle which readily receives and firmlylocks the prongs of an electrical plug therein, and which cannot becomeaccidentally disconnected when the plug cord is subjected to accidentaljerks or pulls such 10 as occur in everyday use.

Another object of the invention is to design a very simple, economical,and substantial recep-- tacle composed of few parts, all of simple yetsturdy construction,- which can be readily manufactiired, and which canbe easily and quickly assembled. s I

A further object is to provide a device of the character described, thebody of which is formed of resilient material, which resiliency isutilized to accomplish the locking and release of the plug.

prongs inserted-therein.

With the above and other objects in view, the

. present invention consists in the combination and arrangement ofparts, hereinafter more fully described,.illustrated in the accompanyingdrawing,

and more particularly. pointed out in the appended claims, it beingunderstood that changes may be made in the form, size, proportion andminor details of construction, without departing from the spirit, orsacrificing any of the advantages of the invention.

In the drawing:

Fig. l is a view of my new electrical receptacle showing also a prongedplug for insertion therein.

4 Fig. 2 is a vertical sectional view'showing the plug prongs locked inthe receptacle.

Fig. 3 is an enlarged detail sectional view, the solid lines showing theprongs locked in thereceptacle, the broken lines showing the position of40 the contact prongs to permit removal and also the.

position wheniiemoveda In the drawing the numeral 5 represents a,standard conventional pronged plug. This is formed of resilientmaterial, (but not necessarily)- andthe face orprong end thereof iscircular in shape and recessed to form a rim 6, the opposite end of theplug being conical in shape as clearly shown in Fig. 1 of the drawing.The plug 5 is centrally bored as at hand opens into an enlarged recess 8in )whichthe prong members 9 are mounted, the inner ends of theprongslbeing bent at right-angles to the main body, and screws in areanchoredtherein and serve to secure the prongs in position, as well asserving as terminals to which the terminal ends .II and I2 respectivelyof the .cord l3 are connected, said cord leading throughthe bore 1 asusual. This is all of conventional design and forms no part of thepresent invention. I wish to direct particular attention to the factthat the 5 prongs 9. are of standard size and shape such as used onconventional plugs at present in general use in the electrical field.

The receptacle is formed as clearly shown in. Figs. 1, 2 and 3 of thedrawing, the body l4 being 10 also 'formed of resilient material, theface being recessed to'forma rim I5, the opposite end being conicalin.,shape, and oppositely disposed bosses iii are provided on the outerwall of the receptacle and serve as .finger grips for a purpose tobe 15presently described. A

The receptacle is provided with an axle bore I! to accommodate theelectric cord 18, said bore opening into an enlarged recess i9 whichaccommodates the spaced contact prongs 20, said 20 prongs beingconnected tb the terminalv ends 2| serves to secure them in properposition, the

upper end section of the'separator being of diniensions 'to "snugly fitthe recess I 9, said recess opening into a, larger recess 24, andthrough i which the contact prongs 20 extend. 3i)

The projecting ends of the prongs 20 are outwardly curved as at 25, andrectangular shaped openings 26 are provided in said curved ends,

. and are of a size to freely accommodate the ceptacle being forcedtogether until the ends are in facial contact and as clearly'shown inFig. 2

of the drawing. Thesqueezing action on the receptacle is thenreleased-and the body springs back to original position,the sharp edgesof the openings theireceptacle. 1 v The release of the plug from thereceptacle is affected in exactly the same manner, itis merely 55 2'6firmly engaging the prongs 9,' and 5 this together with the curvature ofsaid contact prongs serves to firmlylock the plug prongs on necessary toplace the fingers on the bosses l6, and squeeze the base body so thatthe upper ends or the contact prongs 20 are forced towards each other,this releases the binding action of the edges of the openings 26 on theprongs 9, and the prongs can then be easily withdrawn.

The resilient locking feature exerts a constant binding action of thecontact prongs on the plug prongs, there is positive electrical contactat all times, and the unlocking action is simple and easy.

A suitable disc or cover. (not shown) is inserted in the end of thereceptacle to form a closure therefor.

Having thus described my invention, what I claimand desire to secure byLetters Patent is:

1. An electrical receptacle the body of which is formed of resilientmaterial, prong contact members mounted therein and having outwardlycurved outer end sections provided with sharpedged slotted openingstherein adapted to accommodate the prongs of a standard plug, and aresilient spacer separating said prong contact members.

2. An electrical receptacle formed of resilient material having prongcontact members mounted therein in spaced relation and formed withoutwardly curved end sections, rectangular shaped openings provided insaid curved end sections and adapted to receive-the prongs of a standardplug, bosses formed integral with said receptacle body and located inpredetermined relationto the inner ends of said contact prongs wherebywhen said bosses are pressed towards each other, the inner ends of theprongs will also be pressed predetermined position, the edges of therectanv gular openings being sharp-edged for gripping and locking thestandard plug prongs in the receptacle when the squeezing action isdiscontinued.

4. An electrical receptacle comprising an inherently resilienthollowed-out body having integral bosses arranged thereon inpredetermined relation, contact prongs mounted in said hollowed-out bodyin predetermined relation to said bosses, resilient means forcing theinner ends of t the prongs from each other, a curved section ofpredetermined radius on the free end of each prong, a rectangular shapedopening in each section, adapted when the bosses are gripped and thebody squeezed, to so space said contact prongs and openings to receivethe prongs of a standard pronged plug, and resilient means between saidcontact prongs for forcing them back to original position when thesqueezing action 1s discontinued.

ARTHUR L. KUHLMAN.

